Add SDK.Player.IsHiding()

[victorpopkov]

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Is your feature request related to a problem? Please describe.

See dstmodders/mod-keep-following#8.

Describe the solution you'd like

The solution in dstmodders/mod-keep-following#8 looks good to me:

local function IsHiding(inst)
    return inst and (inst.sg and inst.sg:HasStateTag("hiding") or inst.HasTag and inst:HasTag("hiding"))
end

Describe alternatives you've considered

If applicable, add a clear and concise description of any alternative solutions or features you've considered.

Additional context

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